<div class="box"></div>
<style>
/* From Uiverse.io by Saiyed-Tanvir - Tags: loader, box, blocky, box-shadow */
.box {
  height: 5cm;
  width: 5cm;
  border: 5px solid #ffa600;
  box-shadow: inset 0 0 0 #ffa600;
  animation: load 2s ease-in-out infinite;
}

@keyframes load {
  0% {
    box-shadow: inset -2.5cm -2.5cm 0 #ffa600;
  }

  25% {
    box-shadow: inset 2.5cm -2.5cm 0 #ffa600;
  }

  50% {
    box-shadow: inset 2.5cm 2.5cm 0 #ffa600;
  }

  75% {
    box-shadow: inset -2.5cm 2.5cm 0 #ffa600;
  }

  100% {
    box-shadow: inset -2.5cm -2.5cm 0 #ffa600;
  }
}
</style>
